DESCRIPTION (APPLICATION ABSTRACT): Legislation to restrict mandatory overtime for nurses in now pending in 14 State legislatures. No one knows if this legislation is needed to protect patient safety or if it is an outgrowth of hospital nurses' dissatisfaction with their working conditions. Since registered nurses are exempt from the federal wage and hour laws governing overtime pay, little is known about the hours worked by hospital staff nurses and the effect of extended work shifts on patient care. Studies have repeatedly shown decreased productivity and increased errors when workers work for prolonged periods and/or at night. Little is known about the effects on patient safety when nurses work for more than eight hours per shift. Patient safety at night is of particular concern, since at least three small studies have shown that approximately one-fourth of nurses working rotating or straight night shifts report struggling to stay awake while caring for patients. Therefore, this study will address staff nurse fatigue and patient safety in two ways. The first phase of the study will focus on describing the hours worked by nurses and the effects of these hours on patient safety by 1) describing the work patterns of hospital staff nurses in terms of hours worked, duration of shifts, and amount of overtime worked; 2) determining how much overtime nurses are working, how often they work overtime, when the overtime occurs (time), and if nurses are required to work overtime; and 3) determining if there is an association between errors and the hours worked by hospital nurses. The second phase will involve designing and testing a fatigue countermeasures program for nurses. This countermeasures program will involved strategies used by other industries to minimize the adverse effects of fatigue, sleep loss, and circadian rhythm disruption, and will be evaluated by pre- and post-test measurements of vigilance and sleep/wake patterns.